remarkable kids. All getting their health back, by breathing in the light, and keep attacks at bay. Juju chang has their inspiring stories. One. Two. Reporter: This little guy is 6-year-old gabe adler. The big guy, richard ploweden. Five-time world champion martial artist. A faceoff between student and master. Richard's not just teaching gabe how to fight. Here at michigan's beaumont children's hospital, they're teaching kids in the fight of their lives. We teach them kicks and punches. But the main thing is therapy, breathing techniques, to help them through their diagnosis. Reporter: These kids are either patients in a cancer ward or have a sibling there. Together, they're using this ancient art to kick cancer. It's the brainchild of an unorthodox rabbi, who happens to be a black belt himself. After losing his own daughter to leukemia, he wanted to help others who were struggling through cancer treatment. You learn that pain is a message. You don't have to listen. You can breathe in this amazing emergency, this chi. Five minutes later, they pulled out the needle. And the boy looked at the nurse and said, did you do it yet? And that's when kicking cancer was born. Reporter: Today, he's 7. He's gone from having to be held down for treatments to managing it all on his own. Makes pain go away. He's informed several nurses on several occasions that he's a big boy and he's a martial artist and he will do it all by himself. Reporter: Amber's mom, michelle, says after a recent surgery, her 12-year-old daughter's mental toughness surprised even a seasoned recovery room nurse. They notice that she started to do the breathing on her own and started calming herself down. And she said, she's been there for 20 years and never saw anyone take that kind of power in their own hands. Reporter: The martial arts teach these kids even though their bodies may feel weak, their bodies can be strong. Here's a time in their lives when they're anything but powerful. We explain to them, you can be powerful. You are powerful. And you're teaching. You're very powerful. Reporter: It's a lesson he hopes they'll use even after they triumph over their illness. And on this day, the students become teachers. Showing the standing room only crowd of adult cancer patients and their families, the secret TO THE THREE Ps. For "good morning america," juju chang, abc news, new york. What a difference the organization is making. Helping more than 5,000 kids all over the world.

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